1. Field of Invention
This invention relates to adjustable eyeglass frames, and more particularly to adjustable eyeglass frames having telescoping ear pieces that are further adapted to rotationally swivel and lock in place for additional comforted.
2. Prior Art
Today, millions of people wear eyeglass frames, and more particularly to filter sunlight, and for safety when working in factories, for example. The two most important aspects of making a usable pair of glasses are the proper grind of the lenses, and the proper sizing of the frame. Although adults usually have minor difficulty in finding proper frames, this is not always the case, especially when the glasses are used on a worksite for safety reasons. These glasses can be used with many different employees and will tend to be difficult to fit the vast majority of employees.
A much larger problem arises when glasses are needed for children. Since children grow quickly, it is possible that a child may outgrow a frame in less than one year. Constantly upsizing eyeglass frames can become expensive. Moreover, in addition to adjusting the length of the temples a need exist for a means to rotationally adjust or swivel the temple member for better fit and comfort.
In the past, several attempts to provide means of adjusting frames have been patented. U.S. Pat. No. 1,252,126, to Letzeisen discloses a frame having a wire temple. The temple was slidably attached to the frame with a locking adjusting screw. This adjusting screw can be loosen to allow the temple to slide back and forth until the desired length of temple is found. The nut can then be locked in place, restraining the temple.
U.S. Pat. No. 1,841,052 to Pollmiller, U.S. Pat. No. 1,751,804 to Fischer, U.S. Pat. No. 2,503,275 to Klienman, and U.S. Pat. No. 2,856,813 to Kudelko all disclose eyeglass adjusters utilizing some type of adjusting screw mechanism to adjust the temples. In these patents, the temples are fitted with an adjusting screw portion fitted into a threaded portion. As the adjusting screw is turned, the earpiece is either extended or retracted from the temple.
Typically, these devices include some type of locking mechanism to provide the temple from moving thereby changing the distance setting. U.S. Pat. Nos. 3,584,938 and 4,153,346 disclose an alternate means of adjusting the temples. These devices utilize sliding bars having discrete position settings to make the adjustments. In these devices, the temple is held with a pin that secures the bar. The pin is then removed, the bar either extended or retracted until a new set position is aligned with the pinhole, and the pin is replaced.
One of the drawbacks to all these devices is that they all must be adjusted when they are off the wearer's head. This requires the wearer or the fitter to place the frame on the wearer's head, check the fit, remove the frame, make an adjustment, check the fit, remove the frame, make adjustments and so on.
Another drawback of the fixed slide-pin devices is that the pins provide fixed sizes, which limit their use in many cases and will not provide exact fits in many cases. Tuttle in U.S. Pat. No. 4,799,782 developed a lengthwise adjustable temple wherein a lengthwise screw could be turned from the front of the glasses and thereby adjust the length only.
It is an object of this invention to provide adjustable glasses that can be adjusted in the temple both lengthwise and rotationally while the user is wearing them.
It is another object of this invention to provide adjustable glasses that have a twist-lock mechanism on each temple as the adjusting mechanism for temple members that have the portion fitting over the ear angulated or circular.
It is yet another object of this invention to provide an adjustment means for glasses that is totally concealed inside the barrel of a twist-lock.
It is yet a further object of this invention to produce adjustable glasses having a swivel or rotational adjustment means that does not interfere with the operation of the temple hinges.
It is yet a further object of this invention to produce adjustable glasses that have a self locking adjustment mechanism for both length and the angle of the earpiece.